In vitro modelling of tongue derived microbial biofilms and their reponse to treatment

This work concerns the development of a flat plate perfusion model to study biofilms derived from human tongue biota. The model has been derived from a previous sorbarod model, via a flat plate model (used to study wound organisms), to the model described in this thesis. The specific technical objectives were; 1. To measure biofilm pH in real time, 2. To extend VOC analysis by SIFT-MS to six biofilms in parallel and 3. To enable photodynamic interventions and optical monitoring of bioluminescent and non-bioluminescent organisms. The specific scientific objectives were; 1. To validate the model by comparison of in vivo and in vitro case studies, 2. To characterise the in vivo biofilm ecology and compare with ecology in vitro, 3. To compare existing and novel anti-malodour preparations and biofilm disrupting agents (including D-amino acids) and 4. To assess and aid the development of a novel handheld surface plasmon resonance based device for measuring oral volatile compounds.The results demonstrated that the biofilms transplanted from human donors are stable and reproducible, and that profiles of volatile compounds are retained in the transplanted biofilm, with high and low malodour individuals producing high and low malodour biofilms (profiles are indistinguishable by χ2 analysis at p < 0.1). The model was used to evaluate a novel formulation which was shown to be more effective than similar active compounds and controls (p < 0.05). In a further experiment, exposure of biofilms to D-amino acids during the growth phase was shown to cause significant (P< 0.05) effects onmicrobial and EPS composition compared with controls.Finally, the model in conjunction with SIFT-MS has been used to assess the performance of a novel surface plasmon resonance based biosensor. This biosensor has been shown to distinguish high and low malodour biofilms both in vitro and in vivo.In conclusion it has been demonstrated that the flat plate perfusion system is a stable, reproducible and accurate model covering many of the main aspects of a real tongue biofilm, and it has many advantages when compared with other published biofilm models

Top Quarks at Photon Colliders

A review of results on top quark physics expected at the Photon Linear Colliders is presented.Comment: 12 pages, 10 figures, talk given at the International Workshop on High Energy Photon Colliders, 14-17 June 2000, Hamburg, German

Celecoxib decreases prostaglandin E\u3csub\u3e2\u3c/sub\u3e concentrations in nipple aspirate fluid from high risk postmenopausal women and women with breast cancer

Background Celecoxib inhibits PGE2 production in cancerous tissue. We previously reported that PGE2 levels in nipple aspirate fluid (NAF) and plasma were not decreased in women at increased breast cancer risk who received celecoxib 200 mg twice daily (bid). The endpoints of the current study were to determine if a short course of celecoxib 400 mg bid would decrease PGE2 levels in women 1) at increased breast cancer risk, and 2) with established breast cancer. Methods NAF and plasma samples were collected before, 2 weeks after taking celecoxib 400 mg bid, and two weeks after washout from 26 women who were at increased breast cancer risk. From 13 women with newly diagnosed breast cancer, NAF from the incident breast and plasma were collected before and on average 2 weeks after taking celecoxib. Additionally, in nine of the 13 women with breast cancer, NAF was collected from the contralateral breast. Results No consistent change in NAF or plasma PGE2 levels was noted in high risk premenopausal women. NAF PGE2 levels decreased after celecoxib administration in postmenopausal high risk women (p = 0.02), and in both the NAF (p = 0.02) and plasma (p = 0.03) of women with breast cancer. Conclusion Celecoxib 400 mg bid taken on average for 2 weeks significantly decreased NAF, but not plasma, PGE2 levels in postmenopausal high risk women, and decreased both NAF and plasma PGE2 levels in women with newly diagnosed breast cancer. PGE2 levels may predict celecoxib breast cancer prevention and treatment efficacy. Our observations are preliminary, and larger studies to confirm and extend these findings are warranted

Physical degrees of freedom in stabilized brane world models

We consider brane world models with interbrane separation stabilized by the Goldberger-Wise scalar field. For arbitrary background, or vacuum configurations of the gravitational and scalar fields in such models, we construct the second variation Lagrangian, study its gauge invariance, find the corresponding equations of motion and decouple them in a suitable gauge. We also derive an effective four-dimensional Lagrangian for such models, which describes the massless graviton, a tower of massive gravitons and a tower of massive scalars. It is shown that for a special choice of the background solution the masses of the graviton excitations may be of the order of a few TeV, the radion mass of the order of 100 GeV, the inverse size of the extra dimension being tens of GeV. In this case the coupling of the radion to matter on the negative tension brane is approximately the same as in the unstabilized model with the same values of the fundamental five-dimensional energy scale and the interbrane distance.Comment: 17 pages, LaTeX, corrected typos, amended the normalization constants of the scalar modes and their coupling constants to matte

Celecoxib concentration predicts decrease in prostaglandin E\u3csub\u3e2\u3c/sub\u3e concentrations in nipple aspirate fluid from high risk women

BACKGROUND: Epidemiologic studies suggest that long term low dose celecoxib use significantly lowers breast cancer risk. We previously demonstrated that 400 mg celecoxib taken twice daily for 2 weeks lowered circulating plasma and breast nipple aspirate fluid (NAF) prostaglandin (PG)E2 concentrations in post- but not premenopausal high risk women. We hypothesized that circulating concentrations of celecoxib influenced PGE2 response, and that plasma levels of the drug are influenced by menopausal status. To address these hypotheses, the aims of the study were to determine: 1) if circulating plasma concentrations of celecoxib correlated with the change in plasma or NAF PGE2 concentrations from baseline to end of treatment, and 2) whether menopausal status influenced circulating levels of celecoxib. METHODS: Matched NAF and plasma were collected from 46 high risk women who were administered celecoxib twice daily for two weeks, 20 subjects receiving 200 mg and 26 subjects 400 mg of the agent. NAF and plasma samples were collected before and 2 weeks after taking celecoxib. RESULTS: In women taking 400 mg bid celecoxib, plasma concentrations of the agent correlated inversely with the change in NAF PGE2 levels from pre- to posttreatment. Nonsignificant trends toward higher celecoxib levels were observed in post- compared to premenopausal women. There was a significant decrease in NAF but not plasma PGE2 concentrations in postmenopausal women who took 400 mg celecoxib (p = 0.03). CONCLUSION: In high risk women taking 400 mg celecoxib twice daily, plasma concentrations of celecoxib correlated with downregulation of PGE2 production by breast tissue. Strategies synergistic with celecoxib to downregulate PGE2 are of interest, in order to minimize the celecoxib dose required to have an effect

Comparing regulatory and non-regulatory indices of early childhood education and care (ECEC) quality in the Australian early childhood sector

This study examines associations between Australia’s regulatory ratings of quality in early childhood education and care (ECEC)—the National Quality Standard (NQS)—and two research-based quality rating scales. The analytic sample consisted of 257 ECEC services across three Australian states. Results indicated (1) modest positive associations between NQS ratings and scale scores; (2) some specificity between NQS quality areas (educational programs and practice; relationships with children) and one research scale—the Sustained Shared Thinking and Emotional Wellbeing (SSTEW) scale; (3) variability in quality scales scores within each NQS designation; and (4) mitigation of these associations when the time-gap between ratings exceeded 24 months. Findings suggest NQS and research scales tap some common core of quality, yet capture different aspects of quality, suggesting both could be used to raise standards of quality in Australian preschools, where the research scales potentiate raising quality to even higher levels than NQS

Energy scales in a stabilized brane world

Brane world gravity looks different for observers on positive and negative tension branes. First we consider the well-known RS1 model with two branes embedded into the AdS_5 space-time and recall the results on the relations between the energy scales for an observer on the negative tension brane, which is supposed to be "our" brane. Then from the point of view of this observer we study energy scales and masses for the radion and graviton excitations in a stabilized brane world model. We argue that there may be several possibilities leading to scales of the order 1-10 TeV or even less for new physics effects on our brane. In particular, an interesting scenario can arise in the case of a "symmetric" brane world with a nontrivial warp factor in the bulk, which however takes equal values on both branes.Comment: 15 pages, corrected typos, enlarged conten

Soy isoflavones have an antiestrogenic effect and alter mammary promoter hypermethylation in healthy premenopausal women1

We hypothesized that soy isoflavones would have dose related estrogenic and methylation effects. 34 healthy premenopausal women were prospectively enrolled and randomized in double-blind fashion to receive either 40 mg or 140 mg isoflavones daily through one menstrual cycle. Breast specific (NAF) and systemic (serum) estrogenic effects were assessed measuring the estrogenic marker complement (C)3 and changes in cytology, while methylation effects were evaluated in mammary ductoscopy (MD) specimens using methylation specific PCR assessment of five genes (p16, RASSF1A, RARβ2, ER, and CCND2) associated with breast carcinogenesis. Serum genistein significantly increased post treatment in women consuming both isoflavone doses. Neither NAF nor MD cytology significantly changed after either low or high dose isoflavones. Serum C3 levels post treatment were inversely related to change in serum genistein (r= -0.76, p=0.0045) in women consuming low dose isoflavones. RARβ2 hypermethylation increased post treatment correlated with the post treatment level of genistein among all subjects (r=0.67, p=0.0017) and in women receiving high dose isoflavones (r=0.68, p=0.021). At the low dose, CCND2 hypermethylation increase correlated with post treatment genistein levels (r=0.79, p=0.011). The inverse correlation between C3 and genistein suggests an antiestrogenic effect. Isoflavones induced dose specific changes in RARβ2 and CCND2 gene methylation which correlated with genistein levels. This work provides novel insights into estrogenic and methylation effects of dietary isoflavones.

Fostering effective early learning (FEEL) study

The 2018 Fostering Effective Early Learning (FEEL) study focuses on the importance of quality, and how to strengthen it in early childhood education and care (ECEC) settings. Extensive research demonstrates that the benefits of ECEC for children are increased when the service provider and educators are highly skilled and participate in professional development (PD), and the service is of high quality. Upskilling the workforce, including in-service professional development, is considered to be a key to improving quality, and can produce substantial and practical improvements for staff and children alike. Building on the existing body of international research, the findings of the Fostering Effective Early Learning (FEEL) study, address the need for quality improvement in ECEC by showing how a particular form of evidence-based in-service PD can produce substantial and practically meaningful improvements in both staff practices and child outcomes. The FEEL study was conducted by the research team from Early Start, University of Wollongong, on behalf on the NSW Department of Education

Measuring interactional quality in pre-school settings: Introduction and validation of the Sustained Shared Thinking and Emotional Wellbeing (SSTEW) scale

Research increasingly acknowledges the importance of high quality interactions that support and extend children’s thinking. Few measurement tools currently exist, however, to capture this specific aspect of process quality. The Sustained Shared Thinking and Emotional Wellbeing (SSTEW) scale was developed to assess interactional quality in early childhood education and care, and it includes dimensions of process quality based on developmental theories and practice in effective settings. This study compared ratings on the SSTEW and Early Childhood Environment Rating Scale – Extension (ECERS-E) to consider the impact of varying levels of curricular and interactional quality on child development in 45 Australian pre-school centres; namely the language, numeracy and socio-behavioural development of 669 children at the end of their pre-school year. Results indicated a level of predictive validity for interactional quality ratings as measured by SSTEW which, while related to curricular quality ratings on ECERS-E, differed in associations across domains of child development